Rich never would have considered coming back, as he thoroughly loved Arizona (the state and UofA).
Tucson is a large progressive city and much nicer than Morgantown in every respect.
However, Rich likely now would return to WVU, as his options are very limited. WVU would take him back in a heartbeat. WVU begged him not leave and has never had any success since he left.
I doubt WVU would take him back in a heartbeat. I think WVU knows that if they re-hired him a sizable segment of the fanbase would revolt and there's just no point in provoking that. Holgs is going to be around for a couple years if not longer and if Holgs does leave then WVU will have plenty of people wanting to coach there, especially hungry young guys looking to make a name.
Considering the way RR was fired from this last job (not just the not-great winning but also the scandal) and that he's no long a hot young coach (mid 50s) I don't think he's going to get another job the caliber of WVU or Arizona or Michigan.
When Bama and Michigan were after RR, RR had the leverage with respect to WVU and he used to maximize benefit to himself instead of being decent about it. He didn't apologize left and right for upsetting people, like Huggs did when he left K-State, rather he screwed people over. But now the tables have turned. It's the classic case of, treat people nice on the way up because someday you might be coming down.